Lung cancer is the most common cause of cancer-related death among both men and women in the United States. Individuals with early-stage lung cancer have markedly reduced exercise capacity caused by multiple mechanisms (e.g., disease pathophysiology, treatment, deconditioning, etc.). This is of critical importance since poor exercise capacity is associated with higher disease-related symptoms, poor health-related quality of life (HRQOL), increased susceptibility to common age-related diseases and likely, premature death. Despite its importance, effective interventions to improve exercise capacity among lung cancer patients are not available. Results from two uncontrolled pilot studies from our group have provided 'proof of principle'that aerobic training is a safe and feasible intervention associated with modest improvements in exercise capacity and HRQOL among early-stage lung cancer patients. The following two questions are now germane: (1) what is the most effective type of exercise training to improve exercise capacity;and (2) what are the mechanisms underlying this improvement? We propose a prospective, four-arm, randomized trial to compare the effects of three different exercise programs relative to a sedentary control group among 150 early-stage lung cancer patients who have completed cancer therapy. This grant will have the following primary and secondary aims: Primary aim: determine the effects of aerobic training and resistance training, relative to attention-control, on exercise capacity. Secondary aims: (1) to determine the effects on patient-reported outcomes, (2) to examine the physiological mediators of the exercise training - VO2peak relationship, (3) to examine the psychological mediators of the intervention - patient-reported outcomes relationship. This study will address several fundamental but, currently unanswered questions regarding the role of exercise training in the management of lung cancer. Information gained from this clinical trial will inform the design in future-planned studies further investigating the role of exercise training across the lung cancer survivorship continuum. Finally, the mechanistic findings will provide insight into how to refine exercise training interventions to maximize improvements in exercise capacity and associated outcomes in this underserved population. PUBLIC HEALTH RELEVANCE: Lung cancer is the most common cause of cancer-related death among both men and women in the United States. Individuals with early-stage lung cancer have markedly reduced exercise capacity caused by multiple mechanisms (e.g., disease pathophysiology, treatment, deconditioning, etc.). This is of critical importance since poor exercise capacity is associated with higher disease-related symptoms, poor health-related quality of life (HRQOL), increased susceptibility to common age-related diseases and likely, premature death. Despite its importance, effective interventions to improve exercise capacity among lung cancer patients are not available.